In my opinion push - thorugh is more deceptive. With that said I think you should learn both because they both have their own advantages and times in which they should be used.
Note that the push-through looks more convincing and has less technical flaws than the original zarrow, but the zarrow doesn't require a cut. That being said, it's easy to put them into context when you know what you need to do. For example, if it were me trying to control the entire deck order in a few riffle shuffles and cuts, here's how I would personally do it:
Push-through
Push-through
Up the ladder
Push-through
Up the ladder
I like to end my riffle shuffle sequences with a few cuts, so that would work fine for me. If, however, you were doing it without a cutting sequence at the end, this would be one such way you could do it:
Push-through
Push-through
Up the ladder
Zarrow
The zarrow would have to be modified slightly, but it's not too hard to figure it out.